1. Field of the Invention
The present invention relates to an endoscope system equipped with a suction channel for inhaling air from an end of a scope section of the endoscope system.
2. Description of the Background Art
A conventional electronic endoscope system equipped with a suction channel for inhaling air from an end of a scope section of the endoscope system has been that in which the turning on and off of the inhalation is controlled by opening and closing of an electromagnetic pinching valve, such that when a suction switch provided on the scope grip portion is pressed down by an operator, the electromagnetic pinching valve is opened and the inhalation at a prescribed inhalation strength is started, whereas when the suction switch is released, the electromagnetic pinching valve is closed and the inhalation stops.
Because of this ON/OFF control at two levels, it has been impossible for a conventional electronic endoscope system equipped with a suction channel to adjust the inhalation strength freely, as had been possible for an old fashioned endoscope equipped with a mechanical valve structure in which the valve had been operated manually through a control lever.